Cleansing (achievement)
From Halopedia, the Halo wiki
Cleansing
Cleansing is an Halo 3 Achievement.
It is earned when someone finishes the Campaign mission Floodgate on the Normal, Heroic, or Legendary difficulties, and gives 30 Gamerpoints to the player.
Note: It is represented by a blue plate with a roman numeral V (five) on it.
The level must be played from mission start in order to unlock the achievement.
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